What is the operating system, including version, you are using?
Please provide a direct link to content that is not working
Opera is based on Chromium, and they have incorporated some of the recent 'block flash by default, click-to-play' changes into Opera 49. I would recommend contacting Opera for assistance as it's the browser that determines when to load the Flash plugin.
I'm using windows 10 pro, version: 1709, build: 16299.19
Please provide a direct link to content that is not working.
In addition to my previous comment, it's quite possible the content provider hasn't updated their content to conform to Opera's 'click-to-play' implementation. Since the browser landscape around 'Flash click-to-play' is very fluid, content developers need to stay abreast of the browser changes. Some do, some don't. I would also recommend reporting the issue to the content provider.
Opera 49 implements click-to-play for Flash Player. It appears to be in line with Chrome's changes (which makes sense, since Opera is a Chromium fork). This is Opera's change, not ours. Please feel free to let them know your thoughts.
The following Chrome guide might be useful: